The present invention relates to signature capture devices and more specifically to a handwriting capture device.
Today, retailers are burdened with having to store and retrieve large amounts of paper records from credit and check transactions. Normally, these records are produced at a retail terminal as master copies of sales receipts, and which are removed from the terminal at the end of the business day for balancing and entry into accounting journals and shipment to processing and storage facilities. Allgeier et al. discloses a write input device employing a display underneath a transparent digitizer to capture signature information. The display gives a customer feedback for stylus input.
While the Allgeier et al. device works well, having a liquid crystal display makes it expensive. Therefore, it would be desirable to eliminate the display and reduce the cost by using a low-cost resistive membrane digitizer. The low-cost resistive membrane must function in response to minimal signing force applied by an ordinary writing instrument such as a pen.
The use of pressure-sensitive resistive membrane digitizers is subject to false actuations, including those caused by finger contact. If the digitizer is shorted by finger contact during signing, the digitized points representing the signature will be obscured by the finger points, resulting in random scribbling in place of the signature.
The sensitivity of a pressure-sensitive digitizer is determined by the density of the spacer dot pattern, which maintains separation between the top and bottom sheets of the digitizer. The more dense the pattern is, the more resistant the digitizer is to finger actuation. However, a high pattern density requires more writing force to capture a signature. In systems without displays or other sources of immediate feedback, it is essential that the digitizer be sensitive to writing force.
Therefore, it would be desirable to provide a handwriting capture device without a display, but having a digitizer sensitive to minimal writing force.